The present disclosure relates to an air conditioner.
Air conditioners are appliances that maintain indoor air at the most proper state according to use and purpose thereof. In general, such an air conditioner includes a compressor, a condenser, an expansion device, and an evaporator. Thus, the air conditioner has a refrigerant cycle in which compression, condensation, expansion, and evaporation processes of refrigerant are performed to cool or heat a predetermined space.
The predetermined space may be variously provided according to a place at which the air conditioner is used. For example, when the air conditioner is disposed in a home or office, the predetermined space may be an indoor space of a house or building. On the other hand, when the air conditioner is disposed in a vehicle, the predetermined space may be a riding space in which a person rides.
When the air conditioner performs a cooling operation, an outdoor heat exchanger provided in an outdoor unit may serve as a condenser, and an indoor heat exchanger provided in an indoor unit may serve as an evaporator. On the other hand, when the air conditioner performs a heating operation, the indoor heat exchanger may serve as a condenser, and the outdoor heat exchanger may serve as an evaporator.
FIG. 1 is a view of an outdoor heat exchanger according to a related art.
Referring to FIG. 1, an outdoor heat exchanger 1 according to the relates art includes a plurality of refrigerant tubes 2 arranged in a plurality of rows, a coupling plate 3 coupled to an end of each of the refrigerant tubes 2 to support the refrigerant tubes 2, and a header 4 through which refrigerant is divided to flow into the refrigerant tubes 2, or the refrigerant passing through the refrigerant tubes 2 is mixed.
Also, the outdoor heat exchanger 1 may further include a return tube 7 for switching a flow direction of the refrigerant from one refrigerant tube 2 to the other refrigerant tube. For example, the return tube 7 may switch a flow direction of the refrigerant from a refrigerant tube, which is disposed in a first row, of the refrigerant tubes 2 arranged in two rows to a refrigerant tube disposed in a second row.
The outdoor heat exchanger 1 may further include a plurality of distributors 5 and 6. The plurality of distributors 5 and 6 include a first distributor 5 through which the refrigerant is divided and introduced into at least one of the plurality of the refrigerant tubes 2 and a second distributor 6 through which the refrigerant is divided and introduced into the rest of the plurality of refrigerant tubes 2.
In the outdoor heat exchanger 1, the refrigerant flows in directions opposite to each other when cooling and heating operations are performed.
For example, when the air conditioner performs a cooling operation, the outdoor heat exchanger 1 functions as a condenser (see a solid arrow).
In detail, a high-pressure refrigerant compressed by the compressor is introduced into the header 4 and divided to flow into the plurality of refrigerant tubes 2, and the divided refrigerant is heat-exchanged with outdoor air while flowing in the refrigerant tubes 2.
The heat-exchanged refrigerant is mixed in the first and second distributors 5 and 6 to flow toward an indoor heat exchanger.
On the other hand, when the air conditioner performs a heating operation, the outdoor heat exchanger 1 functions as an evaporator (see a dotted arrow).
In detail, refrigerant condensed in the indoor heat exchanger may be decompressed while passing through the expansion device and then be introduced into the outdoor heat exchanger 1. The refrigerant is divided to flow into the first and second distributors 5 and 6 at an inlet-side of the outdoor heat exchanger 1 and introduced into the refrigerant tubes 2 through a plurality of branch tubes respectively connected to the distributors 5 and 6.
Here, the refrigerant may be heat-exchanged with the outdoor air while flowing in the refrigerant tubes 2. The heat-exchanged refrigerant may be mixed in the header 4 to flow to a compressor-side.
When the air conditioner performs the cooling operation, the refrigerant passing through the outdoor heat exchanger 1 is in a high-temperature high-pressure gaseous state. Here, in order to increase condensation efficiency of the refrigerant, the number of branch paths branched into the outdoor heat exchanger 1 may be reduced, and the branch paths may increase in length.
That is, when a flow path of the refrigerant increases in length, the refrigerant increases in flow rate to reduce a condensation pressure, thereby improving condensation efficiency, i.e., a ratio in which the refrigerant changes into gaseous phase.
On the other hand, when the air conditioner performs a heating operation, the refrigerant passing through the outdoor heat exchanger 1 is in a two-phase state. Here, to reduce a pressure loss of the refrigerant, the number of branch paths branched into the outdoor heat exchanger 1 needs to increase, and the length of each of the branch paths needs to shorten.
That is, a gaseous refrigerant of the refrigerant in two-phase has a relatively large pressure loss while flowing However, when the flow path of the refrigerant has a short length, and the number of branch paths increases, the pressure loss, i.e., reduction of an evaporation pressure may be prevented to improve evaporation efficiency.
However, according to the structure of the outdoor heat exchanger according to the related art as illustrated in FIG. 1, when the air conditioner performs the cooling and heating operations, since the branch paths through which the refrigerant is divided to flow into the outdoor heat exchanger have the same number and length, the air conditioner according to the related art may be reduced in heat-exchange efficiency.
That is, when the cooling operation is performed, the condensation pressure in the outdoor heat exchanger increases to deteriorate condensation efficiency. When the heating operation is performed, the evaporation pressure in the outdoor heat exchanger decreases to deteriorate evaporation efficiency.